Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Amount of cost to be recognized for option under share-based payment arrangement.

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The number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan.

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Gross number of share options (or share units) granted during the period.

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Number of options outstanding, including both vested and non-vested options.

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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Weighted average price at which grantees could have acquired the underlying shares with respect to stock options that were terminated.

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Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

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Weighted average remaining contractual term for option awards outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Share-based Compensation - Stock Option Activity Under 2019 Incentive Award Plan (Details) - USD ($) $ / shares in Units, $ in Millions		3 Months Ended		6 Months Ended		12 Months Ended
	Jul. 21, 2023	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023	Dec. 31, 2023
Options, Weighted Average Exercise Price
Share-based compensation expense		$ 1.7	$ 1.1	$ 3.3	$ 2.5
ABP Sub Inc. 2019 Incentive Award Plan
Options, Number of Shares
Outstanding, beginning of period				3,515,219
Options granted						0
Options forfeited				(63,748)
Outstanding, end of period		3,451,471		3,451,471		3,515,219
Options, Weighted Average Exercise Price
Outstanding, beginning of period				$ 10.00
Options granted	$ 10.00
Options forfeited				10.00
Outstanding, end of period		$ 10.00		$ 10.00		$ 10.00
Weighted average remaining contractual life of options outstanding				6 years 7 months 6 days		7 years 1 month 6 days
Share-based compensation expense	$ 1.0
Unrecognized compensation expense related to non-vested stock options		$ 3.1		$ 3.1		$ 4.9
Weighted-average remaining requisite service period for which unrecognized compensation expense				7 months		10 months
ABP Sub Inc. 2019 Incentive Award Plan \| Stock options
Options, Weighted Average Exercise Price
Share-based compensation expense		$ 0.8	$ 1.6	$ 1.1	$ 2.5